1. Field of the Invention
The present invention relates to a data processing apparatus, a data processing method, and a program, and, more particularly to, for example, a data processing apparatus, a data processing method, and a program that make it possible to appropriately perform variable speed reproduction including so-called scrub.
2. Description of the Related Art
In recent years, as AV apparatuses such as a recorder and a video camera that treat image data of moving images, AV apparatuses that can treat HD (High Definition) image data have been realized both for the broadcasting industry and for consumer use.
In such AV apparatuses, for example, HD image data is encoded by the MPEG (Moving Picture Experts Group) 2 system, the MPEG IMX50 system, and the like in a unit of long GOP (Group Of Picture) (HD Long GOP). Encoded data obtained as a result of the encoding is recorded in recording media such as a tape, a hard disk, and an optical disk. Further, in the AV apparatuses, the encoded data recorded in the recording media is subjected to MPEG decoding and (an image corresponding to) image data obtained as a result of the MPEG decoding is outputted to a display and displayed.
The long GOP is, for example, a GOP having fifteen or more pictures as one GOP. The MPEG IMX50 system is an encoding system having a maximum bit rate of 50 Mbps and conforming to MPEG2 4:2:2 P@ML. A format of the MPEG IMX50 system is approved by the SMPTE (Society of Motion Picture and Television Engineers) and registered in SMPTE365M as a D-10 format. In the MPEG IMX50 system, all pictures are encoded as I pictures.
As the AV apparatuses, other than the recorder and the video camera, there is an editing apparatus that edits a moving image (including an editing program (software) that is executed by a computer to cause the computer to function as an editing apparatus).
The editing apparatus that edits a moving image has, in general, a function of scrub for allowing a user (an editor) to check contents of the moving image and search for a so-called edition points (an in point and an out point).
Scrub means reproduction of a frame or a field that is a picture designated by the user. The user designates a picture by, for example, performing operation such as movement of a dial serving as a GUI (Graphical User Interface).
In the editing apparatus having the function of scrub, for example, a frame is designated according to a position of the dial and reproduced. Therefore, when the user performs operation for slowly moving the dial, since a frame designated by (a position of) the dial slowly changes, so-called slow reproduction is performed. When the user performs operation for quickly moving the dial, since a frame designated by the dial quickly changes, so-called high-speed reproduction is performed. Moreover, when the user does not move the dial, since a frame designated by the dial does not change, so-called still reproduction is performed (the editing apparatus is in a pause state). Therefore, it can be said that the scrub is a kind of variable speed (special) reproduction.
In a technique proposed in JP-A-11-331754, an image having a high resolution is recorded in a random-accessible first recording medium, an image having a low resolution corresponding to the image recorded in the first recording medium is recorded in a second recording medium, the image having a low resolution recorded in the second recording medium is displayed in normal reproduction, and the image having a high resolution recorded in the first recording medium is displayed at the time of a pause.